Aymen El Arrouji

Backend services for real-time communication and secure file uploads in a team-built pharmacy platform.

• • FastAPI and asynchronous SQLAlchemy
• • PostgreSQL-backed chat service
• • WebSockets with JWT cookie authentication
• • Reconnect handling with exponential backoff
• • Pending-message synchronization
• • libmagic file-content validation
• • Row-locked per-user upload quotas

An asynchronous HTTP/1.1 server built from scratch in C++98 without a web framework.

• • Non-blocking I/O using epoll
• • Persistent HTTP/1.1 connections
• • Chunked transfer encoding
• • CGI execution
• • Custom error pages
• • Virtual hosts and location blocks
• • Method restrictions and body-size limits

This project taught me to treat a server as an event-driven state machine that must handle partial reads, slow clients, malformed requests, connection lifecycles, and cleanup.

A Redis-style server implementing RESP, persistence, snapshots, TLS, and LRU eviction.

• • RESP protocol over epoll
• • TLS 1.3 connections
• • String, list, and hash commands
• • Write-ahead logging with group commit
• • Fork-based snapshots
• • LRU eviction using a hashmap and doubly linked list

I focused on the parts that make a key-value server reliable: protocol handling, durable writes, snapshots, expiration, eviction, and network connection management.

A multi-service web infrastructure built from scratch with Docker Compose, NGINX, MariaDB, WordPress, and TLS.

• • Separate NGINX, WordPress/PHP-FPM, and MariaDB containers
• • TLS 1.2/1.3-only HTTPS gateway
• • Plain HTTP traffic rejected at the gateway
• • Persistent database and upload volumes
• • Services built from Alpine/Debian base images

This project demonstrates the operational side of backend systems: isolation, secure traffic, persistent data, and reproducible environments.